Study of Current and Displacement Stiffness Characteristics of AMB System

The current and displacement stiffness are analyzed toward radical magnetic bearing and thrust magnetic bearing with differential driving mode. The effects of current and displacement stiffness on AMB system are studied to ensure its stable operation. The study indicated that current and displacement stiffness are constant in the range of allowable engineering error. There is a linear range to the magnetic force. The simplified linear model meets the requirement of controller design. The more precise the control precision is, the smaller the linear range is. The research provides a theoretical base of controller design, which is useful for understanding AMB system performance in operation range.